1. Field of the Invention
The present invention relates to Universal Serial Bus (USB) Mass Storage control, and more particularly, to a method for controlling power consumption of a USB Mass Storage, an associated personal computer, and a storage medium storing an associated USB Mass Storage driver.
2. Description of the Prior Art
When a USB Mass Storage such as a card reader is electronically connected to a host device such as a personal computer, the host device typically continues to provide the USB Mass Storage with power. If the USB Mass Storage is kept idle for a long period without being utilized by the user, the host device still continues to provide power, causing unnecessary power consumption.
According to the related art, there is no USB selective suspend control available for the USB Mass Storage. Compared to many complicated devices such as cameras and Human Interface Devices (HIDs), the control available for the USB Mass Storage is limited since the USB Mass Storage is typically controlled with the Small Computer System Interface (SCSI) protocol, rather than means of newer standards. As an Operating System (OS) should comply with the SCSI protocol to properly control the USB Mass Storage, even a dominant Operating System (OS) provider can do nothing with the OS.
In a situation where the personal computer is a laptop computer (i.e. the so-called “notebook”), the unnecessary power consumption mentioned above is really an issue since the laptop computer is supplied by a battery. Thus, a novel method is required for reducing the unnecessary power consumption of the USB Mass Storage.